Evaluate the following expression when $y = 2$ and $x = 6$. $5$ $y$ $ + 7$ $x$ $ - 9$
Answer: Substitute $2$ for ${y}$ and $6$ for ${x}$ $ = 5{(2)} + 7{(6)} - 9 $ $ = 10 + 42 - 9 $ $ = 43$